methallyl chloride
{{Chembox
| ImageFile = MethallylCl.png
| ImageSize =
| ImageAlt =
| PIN = 3-Chloro-2-methylprop-1-ene
| OtherNames = Isobutenyl chloride
|Section1={{Chembox Identifiers
| CASNo = 563-47-3
| PubChem = 11241
| KEGG = C19363
| ChEBI = 82419
| ChemSpiderID = 21106501
| EC_number = 209-251-2
| RTECS = UC8050000
| UNNumber = 2554
| UNII = 7A9X1C3I3O
| ChEMBL = 157368
| StdInChI=1S/C4H7Cl/c1-4(2)3-5/h1,3H2,2H3
| StdInChIKey = OHXAOPZTJOUYKM-UHFFFAOYSA-N
| SMILES = CC(=C)CCl}}
|Section2={{Chembox Properties
| C=4|H=7|Cl=1
| Appearance = Colorless liquid
| Density = 0.9210 g/cm3 (15 °C)
| MeltingPt =
| BoilingPtC = 71-72
| Solubility = }}
|Section3={{Chembox Hazards
| MainHazards =
| FlashPtC = -12
| AutoignitionPtC = 540
| GHSPictograms = {{GHS02}}{{GHS05}}{{GHS06}}{{GHS07}}{{GHS08}}{{GHS09}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|225|302|314|317|331|335|336|351|361|372|373|411}}
| PPhrases = {{P-phrases|201|202|210|233|240|241|242|243|260|261|264|270|271|272|273|280|281|301+312|301+330+331|302+352|303+361+353|304+340|305+351+338|308+313|310|311|312|314|321|330|333+313|363|370+378|391|403+233|403+235|405|501}}
}}
}}
Methallyl chloride is the organic compound with the formula CH2=C(CH3)CH2Cl. It is a colorless liquid and a lacrymator. Its properties are similar to those of allyl chloride. It is a strong alkylating agent used to install isobutenyl groups.{{Cite encyclopedia |title=Methallyl chloride |encyclopedia=e-EROS Encyclopedia of Reagents for Organic Synthesis |last1=Krook |first1=Mark A. |date=2007 |pages=1–6 |doi=10.1002/9780470842898.rm061.pub2 |isbn=978-0471936237 |last2=O'Doherty |first2=George A. |last3=Gao |first3=Dong}}
Reactivity
It is also a precursor to methallyl ligand. It is an isomer of crotyl chloride.
Methylenecyclopropane can be synthesised via an intramolecular cyclisation reaction from methallyl chloride by treatment with a strong base such as sodium amide.{{Cite journal |last1=Salaun |first1=J. R. |last2=Champion |first2=J. |last3=Conia |first3=J. M. |date=1977 |title=Cyclobutanone from Methylenecyclopropane via Oxaspiropentane |journal=Organic Syntheses |volume=57 |pages=36 |doi=10.15227/orgsyn.057.0036}}
{{Gallery |mode=packed |align=center |height=100
|File:Methylenecyclopropane prepn.png
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